Understanding Positive and Negative Slope: A Visual Guide

The Organic Chemistry Tutor

This clear, high-contrast instructional video provides a visual and algebraic explanation of slope, specifically focusing on the difference between positive, negative, zero, and undefined slopes. The narrator breaks down the fundamental definition of slope as "rise over run" (change in y divided by change in x) and uses dynamic visual diagrams to demonstrate how changes in rise and run affect the steepness of a line. A key feature of this video is its use of trigonometry (tangent/arctangent) to connect slope values to specific angles in degrees, offering a deeper conceptual understanding than standard Algebra 1 tutorials. The video culminates in a comprehensive "starburst" diagram that simultaneously displays lines with slopes of 0, 1, 2, 3, undefined, -1, -2, and -3, allowing students to visually compare steepness and direction relative to the origin. For educators, this resource serves as an excellent bridge between basic graphing concepts and more advanced trigonometric applications. It is particularly useful for visual learners who need to see how numerical slope values correspond to the physical "steepness" of a line. The clean blackboard style makes it easy to replicate the diagrams in class, and the inclusion of the angle calculations provides a natural extension for advanced students or geometry classes.